In electrical stimulation therapy (EST), the contraction of muscle is artificially induced by electrical signals.
Electrical muscle stimulation (EMS), a kind of EST, is a training tool used for athletes or ordinary people to help patients who can not move their body parts or whole bodies to recover or not to suffer from secondary symptoms, or to help athletes to recover after exercise.
In recent years, EMS has also been used for beauty purposes in addition to training and treatment purposes. Since the effect of correcting the body shape can be obtained by strengthening muscle, EMS is being increasingly introduced into the field of training for beauty purposes and is also highly effective in obtaining an additional effect of calorie consumption.
In the related art, patch type devices are mainly used for EMS. However, it is difficult to carry such a patch type device having a large oscillator, thereby limiting places where a user can exercise after attaching patches thereto. In addition, as the number of body parts to which patches are attached increases, the number of electric wires for connecting an oscillator to the patches increases, thereby limiting exercise.
To address these problems, the inventors of the present invention have proposed a functional garment for electrical stimulation in Korean Patent Application No. 2016-0121727.
In the disclosed technique, power lines are formed on a garment fabric by coating the garment fabric with electrically conductive liquid silicone rubber containing electrically conductive particles of, for example, copper or silver, and curing the electrically conductive liquid silicone rubber.
Since the power lines are based on silicone rubber, the power lines are flexible when a user wearing the functional garment exercises or moves, thereby maintaining their power line function. However, the electrical conductivity of the power lines varies as the power lines expand and contract.
The reason for this is as follows: since the electrically conductive particles dispersed in the silicone rubber generally have a spherical shape, the density of the electrically conductive particles is uniform before the power lines are stretched but is varied when the power lines are stretched, causing variations in the electrical conductivity of the power lines. In particular, if the density of the electrically conductive particles becomes very low at a particular portion when the power lines are stretched, the supply of power may be interrupted due to the particular portion, and thus the power lines may not function as power lines.
In addition, it is necessary to form an additional insulative film on the power lines to prevent a wearer from being exposed to the power lines, and thus an additional process has to be performed to form the insulative film.
In addition, if external force such as rubbing force is applied to the power lines, the silicone rubber coating may be easily separated and damaged.